[Relationship between sleep quality and bone mineral density in urban residents]

To investigate the relationship between sleep quality and bone mineral density (BMD) in urban residents.

Data of 28 756 Han adults (14 355 males and 14 401 females), who completed both Pittsburgh sleep quality index (PSQI) assessment and radial BMD tests by dual energy X-ray absorptiometry in the Health Management Center of Southwest China University from June 2012 to June 2019 were retrospectively analyzed. The degree of sleep disorder was determined based on PSQI scores, while osteopenia and osteoporosis was diagnosed according to BMD T-value. The χ² test and multiple regression model were used to investigate the relationship between sleep quality and BMD.

The numbers of normal BMD, osteoponia and osteoporosis were 17 039 (59.3%), 7916(27.5%) and 3801(13.2%), respectively. The mean PSQI score was 5.6±1.4 points. According to PSQI scores, there were 15 936 subjects without sleep disorder (55.4%), 5965 with mild (20.7%), 4897 with moderate (17.0%) and 1958 with severe sleep disorder (6.8%), respectively. There was no significant difference in osteoponia/osteoporosis rate between subjects with mild sleep disorder and normal ones (χ²=0.948, P>0.05), while the rate of osteoporosis in moderate sleep disorder group was higher than that in mild group (χ²=525.583, P<0.01), and the rate of osteoponia/osteoporosis in severe sleep disorder group was much higher than that in moderate group (χ²=1124.877, P<0.01). Multiple regression results showed that female, elders, mental labor, smoking and higher PSQI scores were independently associated with lower T-value (all P<0.05), while moderate to intense daily physical activity was associated with higher T-value (P<0.05).

Sleep disturbances may be a major risk factor for BMD loss in urban residents, indicating that it would be a potential target of osteoporosis prevention.